Butalewicz Jamie P, Sanders James D, Clowers Brian H, Brodbelt Jennifer S
Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States.
Department of Chemistry, Washington State University, Pullman, Washington 99164, United States.
J Am Soc Mass Spectrom. 2023 Jan 4;34(1):101-108. doi: 10.1021/jasms.2c00274. Epub 2022 Dec 5.
Coupling drift tube ion mobility (IM) to Fourier transform mass spectrometry (FT-MS) affords the opportunity for gas-phase separation of ions based on size and conformation with high-resolution mass analysis. However, combining IM and FT-MS is challenging because ions exit the drift tube on a much faster time scale than the rate of mass analysis. Fourier transform (FT) and Hadamard transform multiplexing methods have been implemented to overcome the duty-cycle mismatch, offering new avenues for obtaining high-resolution, high-mass-accuracy analysis of mobility-selected ions. The gating methods used to integrate the drift tube with the FT mass analyzer discriminate against the transmission of large, low-mobility ions owing to the well-known gate depletion effect. Tristate gating strategies have been shown to increase ion transmission for drift tube IM-FT-MS systems through implementation of dual ion gating, controlling the quantity and timing of ions through the drift tube to reduce losses of slow-moving ions. Here we present an optimized set of multiplexing parameters for tristate gating ion mobility of several proteins on an Orbitrap mass spectrometer and further report parameters for increased ion transmission and mobility resolution as well as decreased experimental times from 15 min down to 30 s. On average, peak intensities in the arrival time distributions (ATDs) for ubiquitin increased 2.1× on average, while those of myoglobin increased by 1.5× with a resolving power increase on average of 11%.
将漂移管离子淌度（IM）与傅里叶变换质谱（FT-MS）联用，为基于离子大小和构象的气相分离提供了高分辨率质量分析的机会。然而，将IM和FT-MS结合具有挑战性，因为离子离开漂移管的时间尺度比质量分析速率快得多。已采用傅里叶变换（FT）和哈达玛变换复用方法来克服占空比不匹配问题，为获得迁移率选择离子的高分辨率、高质量准确度分析提供了新途径。由于众所周知的门耗尽效应，用于将漂移管与FT质量分析仪集成的门控方法会歧视大的、低迁移率离子的传输。三态门控策略已被证明可通过实施双离子门控来提高漂移管IM-FT-MS系统的离子传输率，通过控制离子通过漂移管的数量和时间来减少慢速移动离子的损失。在此，我们展示了一组优化的复用参数，用于在轨道阱质谱仪上对几种蛋白质进行三态门控离子淌度分析，并进一步报告了提高离子传输率和淌度分辨率以及将实验时间从15分钟缩短至30秒的参数。平均而言，泛素到达时间分布（ATD）中的峰强度平均增加了2.1倍，而肌红蛋白的峰强度增加了1.5倍，分辨率平均提高了11%。
